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1.
Chembiochem ; : e202400640, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39383297

RESUMO

Multidrug Resistance (MDR) can be considered one of the most frightening adaptation types in bacteria, fungi, protozoa, and eukaryotic cells. It allows the organisms to survive the attack of many drugs used in the daily basis. This force the development of new and more complex, highly specific drugs to fight diseases. Given the high usage of medicaments, poor variation in active chemical cores, and self-medication, the appearance of MDR is more frequent each time, and has been established as a serious medical and social problem. Over the years it has been possible the identification of several genes and proteins responsible for MDR and with that the development of blockers of them to reach MDR reversion and try to avoid a global problem. These mechanisms also have been observed in cancer cells, and several calcium channel blockers have been successful in MDR reversion, and the maleimide can be found included in them. In this review we explore the history, mechanisms, reversion efforts, and we specifically focused on the maleimide synthesis as MDR-reversers in co-administration, as well as their biological applications in a urge to expand the available information and explore a very plausible MDR reversion source.

2.
Lipids Health Dis ; 23(1): 303, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39300559

RESUMO

BACKGROUND: Remnant cholesterol (RC), a potent atherogenic lipid, has been shown to be strongly correlated with insulin resistance and the pathogenesis of diabetes mellitus. However, the relationship between RC and normoglycemia reversal in individuals with impaired fasting glucose (IFG) is crucial and remains unclear. This investigation, which aimed to clarify this association, is important for understanding and potentially improving the management of diabetes. METHOD: This study, which included 15,019 IFG participants from 11 Chinese cities between 2010 and 2016, was conducted with a rigorous research process. Cox regression analysis revealed intriguing findings regarding the relationship between RC and normoglycemia reversal in individuals with IFG. Potential nonlinear associations were further explored via smooth curve-fitting techniques and 4-knot restricted cubic spline functions, ensuring a comprehensive analysis. To examine the validity of the results, an array of subgroup and sensitivity analyses were conducted, further bolstering the robustness of the findings. RESULTS: By the end of the 2.89-year median follow-up period, 6,483 of the 15,019 IFG participants (43.17%) had reverted to normoglycemia. The findings, which reveal that increased RC levels are inversely associated with the likelihood of normoglycemia reversal, are novel and significant. According to the fully adjusted Cox proportional hazards model analysis, an increase of one standard deviation in RC was associated with a 20% decrease in the likelihood of normoglycemia reversal among IFG participants (HR: 0.80, 95% CI: 0.77-0.82). A nonlinear association between RC and normoglycemia reversal was observed, with an inflection point at 41.37 mg/dL. This suggests that the growth rate of the likelihood of reversion decreased and stabilized after the inflection point was reached. Moreover, significant interactions were observed between the age groups, providing a more nuanced understanding of this complex relationship. CONCLUSION: Among Chinese adults with IFG, RC exhibited a negative nonlinear relationship with the probability of normoglycemia reversal. When RC levels reached or exceeded 41.38 mg/dL, the probability of achieving normoglycemia progressively diminished and subsequently stabilized. Maintaining RC levels below 41.38 mg/dL can significantly improve the probability of normoglycemia reversal among individuals with IFG, especially those aged 60 years or older.


Assuntos
Glicemia , Colesterol , Jejum , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Glicemia/metabolismo , Colesterol/sangue , Jejum/sangue , Modelos de Riscos Proporcionais , Adulto , Idoso , Estudos de Coortes , Triglicerídeos/sangue , China/epidemiologia , Resistência à Insulina , Intolerância à Glucose/sangue
3.
Access Microbiol ; 6(9)2024.
Artigo em Inglês | MEDLINE | ID: mdl-39239566

RESUMO

Introduction. Mycobacterium tuberculosis (MTB) infections continue to have a high mortality and morbidity burden globally. Interferon-gamma release assays such as Quantiferon Gold Plus (QFG-Plus) aid in diagnosis of latent TB but diagnosis of pleural TB remains challenging. We present a case of active pleural MTB infection with reversion from positive to negative of IGRA result as well as negative Xpert MTB/RIF Ultra PCR result from tissues obtained from pleural biopsy. Case summary. A 52-year-old otherwise healthy male presented in August 2022 with a 2 week history of pleuritic chest pain associated with modest elevation in inflammatory markers. The patient had had a positive QFG-Plus result in 2018, however QFG-Plus during this admission was negative. Computed-tomography pulmonary angiogram and needle thoracocentesis showed an exudative left pleural effusion with predominant lymphocytes. The patient's symptoms failed to resolve with empiric antimicrobial therapy for community-acquired pneumonia. Broncho-alveolar lavage as well as biopsies of pleural tissues via video-assisted thoracoscopic surgery from the left lower lobe yielded negative results on routine microbiological culture as well as Xpert Ultra PCR. Growth of acid-fast bacilli was noted from mycobacterial cultures of pleural tissues which was identified as MTB. Conclusion. Despite significant technological advances, microbiological diagnosis of MTB infections remains challenging. We document QFG-Plus reversion during development from latent to active pleural TB. Decline in the ability of CD4+ and CD8+ T cells to produce interferon gamma in response to TB antigens (ESAT-6 and CFP-10) was likely associated with loss of host control of latent MTB. This case serves as a reminder that despite exhaustive testing with state-of-art diagnostic platforms, MTB infections can still elude discovery.

4.
Biosystems ; 246: 105347, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39349133

RESUMO

Influenza A H5N1 hemagglutinin (HA) plays a crucial role in viral pathogenesis and changes in the HA receptor binding domain (RBD) have been attributed to alterations in viral pathogenesis. Mutations often occur within the HA which in-turn results in HA structural changes that consequently contribute to protein evolution. However, the possible occurrence of mutations that results to reversion of the HA protein (going back to an ancestral protein conformation) which in-turn creates distinct HA structural patterns across the 1959-2023 H5N1 viral evolution has never been investigated. Here, we generated and verified the quality of the HA models, identified similar HA structural patterns, and elucidated the possible variations in HA RBD structural dynamics. Our results show that there are 7 distinct structural patterns occurring among the 1959-2023 H5N1 HA models which suggests that reversion of the HA protein putatively occurs during viral evolution. Similarly, we found that the HA RBD structural dynamics vary among the 7 distinct structural patterns possibly affecting viral pathogenesis.

5.
Arch Microbiol ; 206(10): 393, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39240318

RESUMO

Middle East respiratory syndrome coronavirus (MERS-CoV) is a zoonotic disease affecting camels and humans. The live attenuated vaccine represents a candidate human vaccine because it can induce strong immune responses in immunized hosts. The attenuated vaccine strain of the highly pathogenic virus can also be used to produce a cell-based vaccine in the BSL2 GMP facility. In this study, we evaluated the reversion potential of pathogenicity to pathogenic wild-type virus to ensure the safety of the live attenuated vaccine strain. We passaged our previously developed cold-adapted live attenuated MERS-CoV vaccine strain at 22 °C (EMC2012-CA22°C) in Vero cells at 37 °C as often as 15 times to determine the potential of pathogenicity reversion in hDPP4 (human dipeptidyl peptidase 4)-transgenic mice, K18-hDPP4. The serial passage of EMC2012-CA22°C in Vero cells at 37 °C up to 15 times did not result in pathogenicity reversion to wild-type MERS-CoV. In K18-hDPP4 mice infected with this virus, no weight loss or mortality was observed, and no virus was detected in tissues such as the lung, kidney, brain, and nasal turbinate. In addition, mice immunized with this virus produced a robust neutralizing antibody response and were fully protected from lethal challenge with wild-type MERS-CoV. The cold-adapted attenuated MERS-CoV vaccine strain (EMC2012-CA22°C) was not reverted to wild-type pathogenic virus after 15 passages in Vero cells at 37 °C.


Assuntos
Temperatura Baixa , Coronavírus da Síndrome Respiratória do Oriente Médio , Vacinas Atenuadas , Vacinas Virais , Animais , Chlorocebus aethiops , Células Vero , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Vacinas Atenuadas/imunologia , Camundongos , Vacinas Virais/imunologia , Vacinas Virais/genética , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Infecções por Coronavirus/imunologia , Camundongos Transgênicos , Humanos , Anticorpos Antivirais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/sangue , Inoculações Seriadas , Dipeptidil Peptidase 4/genética , Feminino
6.
Microbiol Spectr ; 12(10): e0117324, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39190636

RESUMO

Klebsiella pneumoniae strains that produce Klebsiella pneumoniae Carbapenemase (KPC) variants displaying resistance to ceftazidime-avibactam (CZA) often remain susceptible to meropenem (MEM), suggesting a potential therapeutic use of this carbapenem antibiotic. However, in vitro studies indicate that these sorts of strains can mutate becoming MEM-resistant, raising concerns about the effectiveness of carbapenems as treatment option. We have studied mutation rates occurring from the reversion of MEM-susceptible KPC-114 to MEM-resistant KPC-2, in CZA-resistant K. pneumoniae belonging to ST11. Two-step fluctuation assays (FAs) were conducted. In brief, initial cultures of KPC-114-producing K. pneumoniae showing 1 µg/mL MEM MIC were spread on Mueller-Hinton agar plates containing 2-8 µg/mL MEM. A second step of FA, at 4-16 µg/mL MEM was performed from a mutant colony obtained at 2 µg/mL MEM. Mutation rates were calculated using maximum likelihood estimation. Parental and mutant strains were sequenced by Illumina NextSeq, and mutations were predicted by variant-calling analysis. At 8 µg/mL MEM, mutants derived from parental CZA-resistant (MIC ≥ 64 µg/mL)/MEM-susceptible (MIC = 1 µg/mL) KPC-114-positive K. pneumoniae exhibited an accumulative mutation rate of 3.05 × 10-19 mutations/cell/generation, whereas at 16 µg/mL MEM an accumulative mutation rate of 1.33 × 10-19 mutations/cell/generation resulted in the reversion of KPC-114 (S181_P182 deletion) to KPC-2. These findings highlight that the reversion of MEM-susceptible KPC-114 to MEM-resistant KPC-2, in CZA-resistant K. pneumoniae ST11 is related to low mutation rates suggesting a low risk of therapeutic failure. In vivo investigations are necessary to confirm the clinical potential of MEM against CZA-resistant KPC variants.IMPORTANCEThe emergence of ceftazidime-avibactam (CZA) resistance among carbapenem-resistant Klebsiella pneumoniae is a major concern due to the limited therapeutic options. Strikingly, KPC mutations mediating CZA resistance are generally associated with meropenem susceptibility, suggesting a potential therapeutic use of this carbapenem antibiotic. However, the reversion of meropenem-susceptible to meropenem-resistant could be expected. Therefore, knowing the mutation rate related to this genetic event is essential to estimate the potential use of meropenem against CZA-resistant KPC-producing K. pneumoniae. In this study, we demonstrate, in vitro, that under high concentrations of meropenem, reversion of KPC-114 to KPC-2 in CZA-resistant/meropenem-susceptible K. pneumoniae belonging to the global high-risk ST11 is related to low mutation rates.


Assuntos
Antibacterianos , Compostos Azabicíclicos , Proteínas de Bactérias , Ceftazidima , Combinação de Medicamentos , Infecções por Klebsiella , Klebsiella pneumoniae , Meropeném , Testes de Sensibilidade Microbiana , Taxa de Mutação , beta-Lactamases , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/enzimologia , Ceftazidima/farmacologia , Compostos Azabicíclicos/farmacologia , beta-Lactamases/genética , beta-Lactamases/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Meropeném/farmacologia , Humanos , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Mutação
7.
Cells Dev ; : 203964, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39151750

RESUMO

The current dogma in cancer biology contends that cancer is an identity problem: mutations in a cell's DNA cause it to "go rogue" and proliferate out of control. However, this largely ignores the role of cell-cell interaction and fails to explain phenomena such as cancer reversion, the existence of cancers without mutations, and foreign-body carcinogenesis. In this proof-of-concept paper, we draw on criminology to propose that cancer may alternatively be conceptualized as a relational problem: Although a cell's genetics is essential, the influence of its interaction with other cells is equally important in determining its phenotype. We create a simple agent-based network model of interactions among normal and cancer cells to demonstrate this idea. We find that both high mutation rates and low levels of connectivity among cells can promote oncogenesis. Viewing cancer as a breakdown in communication networks among cells in a tissue complements the gene-centric paradigm nicely and provides a novel perspective for understanding and treating cancer.

8.
Plant Cell Physiol ; 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39119682

RESUMO

Light affects almost every aspect of plant development. It is perceived by photoreceptors, among which phytochromes (PHY) are responsible for monitoring the red and far-red spectrum. Arabidopsis thaliana possesses five phytochrome genes (phyA-E). Whereas functions of phyA and phyB are extensively studied, our knowledge on other phytochromes is still rudimentary. To analyze phyD function we expressed it at high levels in different phytochrome-deficient genetic backgrounds. Overexpressed phyD-YFP can govern effective light signaling but only at low temperature and in cooperation with functional phyC. Under these conditions, phyD-YFP accumulates to high levels and opposite to phyB, this pool is stable in light. By comparing the photoconvertible phyD-YFP and phyB levels and their signaling in continuous and pulsed irradiation, we showed that phyD-YFP is a less efficient photoreceptor than phyB. This conclusion is supported by the facts that only a part of the phyD-YFP pool is photoconvertible and thermal reversion of phyD-YFP is faster than that of phyB. Our data suggest that the temperature-dependent function of phyD is based on the amount of phyD protein and not on its Pfr stability, as described for phyB. We also found that phyD-YFP and phyB-GFP associate with strongly overlapping genomic locations and mediate similar changes in gene expression, however the efficiency of phyD-YFP is lower. Based on these data we propose that under certain conditions, synergistic interaction of phyD and phyC can substitute phyB function in seedlings and in adult plants, thus increases the ability of plants to respond more flexibly to environmental changes.

9.
Macromol Rapid Commun ; : e2400474, 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39096154

RESUMO

[2π + 2π]-photocycloadditions and their ability to trigger controlled and reversible photoligation through disparate wavelengths provide an attractive platform to unlock advanced functionalities in soft materials. Yet, among the limited amount of functional motifs enabling reversible photoreactions, cyclability is often overlooked due to poor reaction yield and orthogonality. In this study, the advantageous photocharacteristics of the previously underexplored N-methyl-quinolinone photoresponsive motif are leveraged to create a covalent gated system, enabling controlled formation and cleavage of covalent bonds on demand. A systematic evaluation of individual cycloadditions and reversions on the molecular scale, including reaction rates, conversions, and photoproducts, allows identification of the required conditions for generating controlled photoreactions with a remarkable degree of cyclability; while, maintaining high reaction yields. Ultimately, these controlled and cyclable reactions are translated to a macromolecular scale, showcasing a comparable performance in initiating reversible photoligation, as observed at the molecular level. In addition, it is also shown that this progressive methodology can be leveraged to gain a comprehensive understanding of cyclability and clarify the factors contributing to its decreasing yield. Overall, unlocking the potential of quinolinone derivatives through this step-by-step approach lays the foundation for the development of highly controlled and responsive polymer materials with unprecedented potential.

10.
Sci Rep ; 14(1): 18098, 2024 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103476

RESUMO

Despite the clear association between remnant cholesterol (RC)and diabetes risk, no study to date has examined the relationship between RC and reversal of prediabetes to normoglycemia. This retrospective cohort study included a total of 15,023 patients with prediabetes who underwent a physical examination between 2010 and 2016. The link between initial RC levels and the reversion from prediabetes to normoglycemia was analyzed using the Cox proportional-hazards regression model. Additionally, the study explored the possible relationship between RC and the probability of returning normoglycemia by applying Cox proportional hazards regression models with cubic spline functions. To address competing risks, a multivariate Cox regression analysis was undertaken, treating the onset of diabetes as a competing risk event for reversing prediabetes to normoglycemia. Additionally, the study incorporated extensive subgroup analyses alongside multiple sensitivity analyses, enhancing the reliability and robustness of the results. After adjusting for covariates, the findings indicated that RC was inversely associated with the likelihood of reverting to normoglycemia (per 5 mg/dL increase, HR = 0.918, 95% CI 0.909-0.927). The analysis also revealed a nonlinear relationship between RC and normoglycemia reversion, with an inflection point at 51.08 mg/dL. For RC values below this inflection point (RC < 50.08 mg/dL), the HR for the probability of returning to normoglycemia was 0.907 (95% CI 0.897-0.917 per 5 mg/dL). Additionally, the competing risks model demonstrated a negative relationship between RC and the reversal of prediabetes to normoglycemia (SHR = 0.92, 95% CI 0.91-0.93). Sensitivity analyses confirmed the robustness and stability of these results. This study demonstrated a negative and non-linear association between RC and the probability of reversion to normoglycemia in Chinese adults with prediabetes. By actively intervening to reduce RC levels, at least to below 51.08 mg/dL, further reduction of RC may significantly increase the probability of returning to normoglycemia from prediabetes.


Assuntos
Colesterol , Estado Pré-Diabético , Humanos , Estado Pré-Diabético/epidemiologia , Feminino , Masculino , Pessoa de Meia-Idade , Colesterol/sangue , Estudos Retrospectivos , Adulto , Glicemia/metabolismo , Glicemia/análise , China/epidemiologia , Modelos de Riscos Proporcionais , Idoso , Triglicerídeos/sangue , Povo Asiático , Fatores de Risco , Estudos de Coortes , População do Leste Asiático , Lipoproteínas
11.
Brain Behav ; 14(7): e3631, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39034358

RESUMO

OBJECTIVES: The objectives of this real-life study were to analyze the reversion of chronic migraine (CM) to episodic migraine (EM) with fremanezumab, evaluate its benefit on the symptomatology, and determine the influence of possible clinical features on the reversion. BACKGROUND: The clinical manifestations of CM have a high impact on the quality of life of patients, and monoclonal antibodies such as fremanezumab are used as prophylactic treatment. METHODS: Diagnosed CM patients treated for at least 3 months with monthly fremanezumab were interviewed. The data to assess efficacy were before treatment and at the time of the interview: monthly headache days (MHDs), daily headache hours (DHHs), monthly symptomatic medication days (MSMDs), percentage of patients with symptomatic medication overuse (SMO), and pain intensity with the numerical rating scale (NRS) score. Possible predictors of reversion were analyzed: percentage of patients treated for at least 12 months, hypertension, diabetes mellitus, depression, anxiety, symptomatic control with non-steroidal anti-inflammatory drugs (NSAIDs), triptans or both, and amitriptyline prophylaxis. RESULTS: A total of 54 patients were included, of whom 40 (74.1%) were converters to EM. There were significant improvements in converters compared to pre-treatment in MHDs (28.0 vs. 5.0 days), as well as on the variables DHHs, MSMDs, and SMO. The percentage of erenumab failures was significantly higher in non-converters than in converters, as was the percentage of patients with anxiety. CONCLUSIONS: High reversion from CM to EM was achieved with fremanezumab and notable symptomatological improvement, establishing previous failure to erenumab and anxiety as possible detrimental factors for reversion.


Assuntos
Transtornos de Enxaqueca , Humanos , Transtornos de Enxaqueca/tratamento farmacológico , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacologia , Toxinas Botulínicas Tipo A/administração & dosagem , Toxinas Botulínicas Tipo A/farmacologia , Doença Crônica , Resultado do Tratamento , Resistência a Medicamentos , Qualidade de Vida
12.
Int Marit Health ; 75(2): 135-136, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38949215

RESUMO

By integrating health coaching into maritime medical clinics, we can provide tailored support to individuals at risk of developing diabetes and empower them to take control of their health.


Assuntos
Estado Pré-Diabético , Humanos , Estado Pré-Diabético/terapia , Medicina Naval/métodos , Diabetes Mellitus Tipo 2/terapia , Diabetes Mellitus Tipo 2/prevenção & controle
13.
Int J Mol Sci ; 25(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-39000162

RESUMO

Cell-based therapies using corneal stromal stem cells (CSSC), corneal keratocytes, or a combination of both suppress corneal scarring. The number of quiescent keratocytes in the cornea is small; it is difficult to expand them in vitro in quantities suitable for transplantation. This study examined the therapeutic effect of corneal fibroblasts reversed into keratocytes (rCF) in a mouse model of mechanical corneal injury. The therapeutic effect of rCF was studied in vivo (slit lamp, optical coherence tomography) and ex vivo (transmission electron microscopy and immunofluorescence staining). Injection of rCF into the injured cornea was accompanied by recovery of corneal thickness, improvement of corneal transparency, reduction of type III collagen in the stroma, absence of myofibroblasts, and the improvement in the structural organization of collagen fibers. TEM results showed that 2 months after intrastromal injection of cells, there was a decrease in the fibril density and an increase in the fibril diameter and the average distance between collagen fibrils. The fibrils were well ordered and maintained the short-range order and the number of nearest-neighbor fibrils, although the averaged distance between them increased. Our results demonstrated that the cell therapy of rCF from ReLEx SMILe lenticules promotes the recovery of transparent corneal stroma after injury.


Assuntos
Lesões da Córnea , Fibroblastos , Animais , Camundongos , Lesões da Córnea/terapia , Lesões da Córnea/patologia , Fibroblastos/metabolismo , Córnea , Ceratócitos da Córnea , Modelos Animais de Doenças , Terapia Baseada em Transplante de Células e Tecidos/métodos , Substância Própria , Tomografia de Coerência Óptica
14.
Clin Infect Dis ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954503

RESUMO

BACKGROUND: Interferon-gamma release assays (IGRA) are widely used for diagnosis of latent tuberculosis infection. However, with repeat testing, IGRA transformation (conversion or reversion) may be detected and is challenging to interpret. We reviewed the frequency of and risk factors for IGRA transformation. METHODS: We screened public databases for studies of human participants that reported the frequency of IGRA transformation. We extracted study and subject characteristics, details of IGRA testing and results. We calculated the pooled frequency of IGRA transformation (and transient transformation) and examined associated risk factors. RESULTS: The pooled frequency of IGRA conversion or reversion from 244 studies was estimated at 7.3% (95% CI 6.1-8.5%) or 22.8% (20.1-25.7%), respectively. Transient conversion or reversion were estimated at 46.0% (35.7-56.4%) or 19.6% (9.2-31.7%) of conversion or reversion events respectively. Indeterminate results seldom reverted to positive (1.2% [0.1-3.5%]). IGRA results in the borderline positive or negative range were associated with increased risk of conversion or reversion (pooled OR: conversion, 4.15 [3.00-5.30]; reversion, 4.06 [3.07-5.06]). BCG vaccination was associated with decreased risk of conversion (0.70, 0.56-0.84), cigarette smoking with decreased risk of reversion (0.44, 0.06-0.82), and female sex with decreased risk of either conversion or reversion (conversion, 0.66 [0.58-0.75]; reversion, 0.46 [0.31-0.61]). CONCLUSIONS: IGRA conversion is less common than reversion, and frequently transient. Research is needed to determine whether individuals with reversion would benefit from tuberculosis preventive treatment. Re-testing of people with indeterminate results is probably not indicated, since indeterminate results seldom revert to positive.

15.
Cell Stem Cell ; 31(7): 949-960, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971147

RESUMO

Tissue regeneration after damage is generally thought to involve the mobilization of adult stem cells that divide and differentiate into progressively specialized progeny. However, recent studies indicate that tissue regeneration can be accompanied by reversion to a fetal-like state. During this process, cells at the injury site reactivate programs that operate during fetal development but are typically absent in adult homeostasis. Here, we summarize our current understanding of the molecular signals and epigenetic mediators that orchestrate "fetal-like reversion" during intestinal regeneration. We also explore evidence for this phenomenon in other organs and species and highlight open questions that merit future examination.


Assuntos
Intestinos , Regeneração , Humanos , Animais , Intestinos/fisiologia , Diferenciação Celular , Feto , Transdução de Sinais
16.
Trends Genet ; 40(9): 747-756, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38853120

RESUMO

The complexity of the brain is closely tied to its nature as a genetic mosaic, wherein each cell is distinguished by a unique constellation of somatic variants that contribute to functional and phenotypic diversity. Postzygotic variation arising during neurogenesis is recognized as a key contributor to brain mosaicism; however, recent advances have broadened our understanding to include sources of neural genomic diversity that develop throughout the entire lifespan, from embryogenesis through aging. Moving beyond the traditional confines of neurodevelopment, in this review, we delve into the complex mechanisms that enable various origins of brain mosaicism.


Assuntos
Encéfalo , Mosaicismo , Humanos , Encéfalo/crescimento & desenvolvimento , Animais , Neurogênese/genética
17.
Front Immunol ; 15: 1345494, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38915393

RESUMO

Background: Type 1 diabetes (T1D) is preceded by a heterogenous pre-clinical phase, islet autoimmunity (IA). We aimed to identify pre vs. post-IA seroconversion (SV) changes in DNAm that differed across three IA progression phenotypes, those who lose autoantibodies (reverters), progress to clinical T1D (progressors), or maintain autoantibody levels (maintainers). Methods: This epigenome-wide association study (EWAS) included longitudinal DNAm measurements in blood (Illumina 450K and EPIC) from participants in Diabetes Autoimmunity Study in the Young (DAISY) who developed IA, one or more islet autoantibodies on at least two consecutive visits. We compared reverters - individuals who sero-reverted, negative for all autoantibodies on at least two consecutive visits and did not develop T1D (n=41); maintainers - continued to test positive for autoantibodies but did not develop T1D (n=60); progressors - developed clinical T1D (n=42). DNAm data were measured before (pre-SV visit) and after IA (post-SV visit). Linear mixed models were used to test for differences in pre- vs post-SV changes in DNAm across the three groups. Linear mixed models were also used to test for group differences in average DNAm. Cell proportions, age, and sex were adjusted for in all models. Median follow-up across all participants was 15.5 yrs. (interquartile range (IQR): 10.8-18.7). Results: The median age at the pre-SV visit was 2.2 yrs. (IQR: 0.8-5.3) in progressors, compared to 6.0 yrs. (IQR: 1.3-8.4) in reverters, and 5.7 yrs. (IQR: 1.4-9.7) in maintainers. Median time between the visits was similar in reverters 1.4 yrs. (IQR: 1-1.9), maintainers 1.3 yrs. (IQR: 1.0-2.0), and progressors 1.8 yrs. (IQR: 1.0-2.0). Changes in DNAm, pre- vs post-SV, differed across the groups at one site (cg16066195) and 11 regions. Average DNAm (mean of pre- and post-SV) differed across 22 regions. Conclusion: Differentially changing DNAm regions were located in genomic areas related to beta cell function, immune cell differentiation, and immune cell function.


Assuntos
Autoanticorpos , Autoimunidade , Metilação de DNA , Diabetes Mellitus Tipo 1 , Progressão da Doença , Ilhotas Pancreáticas , Humanos , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/genética , Feminino , Masculino , Autoimunidade/genética , Ilhotas Pancreáticas/imunologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Criança , Adolescente , Estudos Longitudinais , Pré-Escolar , Estudo de Associação Genômica Ampla , Epigênese Genética
18.
Adv Sci (Weinh) ; 11(29): e2309889, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38838096

RESUMO

Spontaneous reversion from mild cognitive impairment (MCI) to normal cognition (NC) is little known. Based on the data of the Genetics of Personality Consortium and MCI participants from Alzheimer's Disease Neuroimaging Initiative, the authors investigate the effect of polygenic scores (PGS) for personality traits on the reversion of MCI to NC and its underlying neurobiology. PGS analysis reveals that PGS for conscientiousness (PGS-C) is a protective factor that supports the reversion from MCI to NC. Gene ontology enrichment analysis and tissue-specific enrichment analysis indicate that the protective effect of PGS-C may be attributed to affecting the glutamatergic synapses of subcortical structures, such as hippocampus, amygdala, nucleus accumbens, and caudate nucleus. The structural covariance network (SCN) analysis suggests that the left whole hippocampus and its subfields, and the left whole amygdala and its subnuclei show significantly stronger covariance with several high-cognition relevant brain regions in the MCI reverters compared to the stable MCI participants, which may help illustrate the underlying neural mechanism of the protective effect of PGS-C.


Assuntos
Disfunção Cognitiva , Humanos , Disfunção Cognitiva/genética , Masculino , Idoso , Feminino , Personalidade/genética , Fatores de Proteção , Herança Multifatorial/genética , Cognição/fisiologia , Imageamento por Ressonância Magnética/métodos , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem
19.
Cancers (Basel) ; 16(11)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38893245

RESUMO

Tumors that spontaneously shrink from unknown causes in tumor regression, and that return to normal cells in tumor reversion, are phenomena with the potential to contribute new knowledge and novel therapies for cancer patient survival. Tumorigenesis is associated with dysregulated phosphate metabolism and an increased transport of phosphate into tumor cells, potentially mediated by phosphate overload from excessive dietary phosphate intake, a significant problem in Western societies. This paper proposes that reduced dietary phosphate overload and reregulated phosphate metabolism may reverse an imbalance of kinases and phosphatases in cell signaling and cellular proliferation, thereby activating autophagy in tumor regression and reversion. Dietary phosphate can also be reduced by sickness-associated anorexia, fasting-mimicking diets, and other diets low in phosphate, all of which have been associated with tumor regression. Tumor reversion has also been demonstrated by transplanting cancer cells into a healthy microenvironment, plausibly associated with normal cellular phosphate concentrations. Evidence also suggests that the sequestration and containment of excessive phosphate within encapsulated tumors is protective in cancer patients, preventing the release of potentially lethal amounts of phosphate into the general circulation. Reducing dietary phosphate overload has the potential to provide a novel, safe, and effective reversion therapy for cancer patients, and further research is warranted.

20.
Diabetol Metab Syndr ; 16(1): 129, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877565

RESUMO

BACKGROUND: Prediabetes is a condition preceding the development of diabetes and is associated with an increased risk of a number of complications. The primary mode of management is thought to be lifestyle modification. Pharmacological therapy, such as glucagon-like peptide-1 receptor agonists (GLP-1RAs), were not well addressed in the literature and were only evaluated in trials as secondary and exploratory outcomes with a limited sample size. Here, GLP-1RAs are evaluated as a comprehensive therapy approach for patients with prediabetes. METHODS: A comprehensive search of Web of Science, SCOPUS, PubMed, and Cochrane was performed on May 5, 2023, to retrieve randomized controlled trials (RCTs) comparing the effect of GLP-1RAs to placebo and/or lifestyle modification on prediabetes reversion to normoglycemia, prevention of overt diabetes, glycemic control, anthropometric parameters, and lipid profiles. Review Manager (RevMan) version 5.4 was used. The quality of RCTs was assessed using the revised version of the Cochrane Risk of Bias Tool. GRADE was performed to evaluate the certainty of evidence. RESULTS: Twelve trials involving 2903 patients in the GLP-1RAs group and 1413 in the control group were included in the meta-analysis. Low quality of evidence revealed that GLP-1RAs significantly increased the incidence of prediabetes reversion to the normoglycemic state [RR = 1.76, 95% CI (1.45, 2.13), P < 0.00001] and moderate quality of evidence showed that GLP-1RAs significantly prevented new-onset diabetes [RR = 0.28, 95% CI (0.19, 0.43), P < 0.00001]. Significant reductions in HbA1c, fasting plasma glucose, body weight, waist circumference, triglycerides, and LDL were observed in the GLP-1RAs arm (P < 0.05). However, higher incidences of gastrointestinal disorders were reported in the GLP-1RAs group (P < 0.05). CONCLUSIONS: GLP-1RAs combined with lifestyle modification proved to be a more effective therapy for managing prediabetic patients than lifestyle modification alone, with a tolerable safety profile. Future guidelines should consider GLP-1RAs as an adjunct to lifestyle modification in the management of prediabetic patients to provide better management and improve treatment adherence.

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